Shelving systems often are designed to be adjustable so as to permit relocation of shelves upon a support frame composed of upright support members. Also, some shelving systems are designed so that the number of shelves can be altered by adding more shelves to or removing shelves from a support frame. This provides versatility to a shelving system and the potential for future expansion of the shelving to provide increased storage capacity as the need arises.
Examples of prior art adjustable shelving systems are disclosed in U.S. Pat. Nos. 3,424,111, 3,523,508, 3,757,705, 3,874,511 and 3,927,769. Some of the prior art adjustable shelving systems comprise upright post members having horizontal grooves and horizontal shelves connected to the grooves of the posts. Each shelf typically has an annular or conical collar formed on each of its corners which are slid down over the end of the posts to a desired height located over a groove in each post. The collars are provided with various mechanisms for bringing them into gripping engagement with the posts with a collar component engaging the selected post groove. Similar constructions to that just described are shown in U.S. Pat. Nos. 3,851,601, 3,912,410, 4,094,417, 4,318,352 and in Design U.S. Pat. Nos. Des. 215,773, Des. 234,906 and Des. 271,297.
Though the just described adjustable shelving systems are versatile, most have one common trait that has provided a distinctly limiting factor. The shelves, or horizontal shelf support elements, have had to be sequentially slid along the upright shelf supporting posts when the shelving is being assembled or when an additional shelf is to be added to or removed from a preassembled shelving structure. Thus, another shelf could not be added to the post framework between previously assembled shelves. Therefore, where it has been desirable to add a shelf to the frame of a previously assembled shelving structure the additional shelf has had to be mounted as the upper-most shelf member in the system unless the previously assembled shelves were removed and relocated. Occasionally this has been impractical where the tops of the post were blocked.
Accordingly, if a practical, versatile and inexpensive shelving system could be devised that overcomes the just described limitations, a distinct advance in the art would be achieved. It is the provision of shelving system and a method of assembling shelving which overcomes these limitations to which the present invention is primarily directed.